From 9cc63f8bcd560c760d0b12e15bba8f81c86237cf Mon Sep 17 00:00:00 2001 From: "Paul E. McKenney" Date: Fri, 14 Aug 2026 15:43:51 -0700 Subject: Merge branches 'expcb.2026.07.24a', 'misc.2026.07.30a', 'rcu-tasks.2026.07.30a', 'srcu.2026.08.11a' and 'torture.2026.08.14a' into HEAD Changes: Make expedited grace periods expedite normal RCU callbacks Miscellaneous fixes: * Improve diagnostic output with character task states. * Mark accesses to inform KCSAN of concurrency design. * Move from kmalloc() to kmalloc_obj(). * Documentation updates. * Improve handling of RCU deferred quiescent states. * Clean up unused function arguments and structure fields. * Reduce show_rcu_gp_kthreads() stack space. Tasks RCU updates: * Clean up after SRCU re-implementation of Tasks Trace RCU. * Mark accesses to inform KCSAN of concurrency design. * Add ->lazy_timer status to diagnostic output. * Remove an unnecessary memory barrier. * Fix a data race, courtesy of KCSAN. * Documentation updates. * Convert cond_resched_tasks_rcu_qs() from macro to static inline function. SRCU updates: * Add Rust helpers for SRCU. * Avoid losing queued work at cleanup_srcu_struct() time. Torture-test updates: * Preparation work for immediate RCU priority deboosting. * Test RCU readers from real interrupt handlers (as opposed to softirq). * Simplify code through use of cpumask_next_wrap(). * Improve diagnostic output with character task states. * Add rcutorture.nwriters parameter to allow lightweight stall testing, and rcutorture.stall_only to make doing so easier. * Test an RCU Tasks Trace grace period implying an RCU grace period. * Make RCU Tasks Trace torturing track reader batches. * Fix a data race, courtesy of KCSAN. * Plug a shuffle_tmp_mask memory leak on kthread spawn failure. --- security/ipe/fs.c | 246 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 246 insertions(+) create mode 100644 security/ipe/fs.c (limited to 'security/ipe/fs.c') diff --git a/security/ipe/fs.c b/security/ipe/fs.c new file mode 100644 index 000000000..076c111c8 --- /dev/null +++ b/security/ipe/fs.c @@ -0,0 +1,246 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) 2020-2024 Microsoft Corporation. All rights reserved. + */ + +#include +#include + +#include "ipe.h" +#include "fs.h" +#include "eval.h" +#include "policy.h" +#include "audit.h" + +static struct dentry *root __ro_after_init; +struct dentry *policy_root __ro_after_init; + +/** + * setaudit() - Write handler for the securityfs node, "ipe/success_audit" + * @f: Supplies a file structure representing the securityfs node. + * @data: Supplies a buffer passed to the write syscall. + * @len: Supplies the length of @data. + * @offset: unused. + * + * Return: + * * Length of buffer written - Success + * * %-EPERM - Insufficient permission + */ +static ssize_t setaudit(struct file *f, const char __user *data, + size_t len, loff_t *offset) +{ + int rc = 0; + bool value; + + if (!file_ns_capable(f, &init_user_ns, CAP_MAC_ADMIN)) + return -EPERM; + + rc = kstrtobool_from_user(data, len, &value); + if (rc) + return rc; + + WRITE_ONCE(success_audit, value); + + return len; +} + +/** + * getaudit() - Read handler for the securityfs node, "ipe/success_audit" + * @f: Supplies a file structure representing the securityfs node. + * @data: Supplies a buffer passed to the read syscall. + * @len: Supplies the length of @data. + * @offset: unused. + * + * Return: Length of buffer written + */ +static ssize_t getaudit(struct file *f, char __user *data, + size_t len, loff_t *offset) +{ + const char *result; + + result = ((READ_ONCE(success_audit)) ? "1" : "0"); + + return simple_read_from_buffer(data, len, offset, result, 1); +} + +/** + * setenforce() - Write handler for the securityfs node, "ipe/enforce" + * @f: Supplies a file structure representing the securityfs node. + * @data: Supplies a buffer passed to the write syscall. + * @len: Supplies the length of @data. + * @offset: unused. + * + * Return: + * * Length of buffer written - Success + * * %-EPERM - Insufficient permission + */ +static ssize_t setenforce(struct file *f, const char __user *data, + size_t len, loff_t *offset) +{ + int rc = 0; + bool new_value, old_value; + + if (!file_ns_capable(f, &init_user_ns, CAP_MAC_ADMIN)) + return -EPERM; + + old_value = READ_ONCE(enforce); + rc = kstrtobool_from_user(data, len, &new_value); + if (rc) + return rc; + + if (new_value != old_value) { + ipe_audit_enforce(new_value, old_value); + WRITE_ONCE(enforce, new_value); + } + + return len; +} + +/** + * getenforce() - Read handler for the securityfs node, "ipe/enforce" + * @f: Supplies a file structure representing the securityfs node. + * @data: Supplies a buffer passed to the read syscall. + * @len: Supplies the length of @data. + * @offset: unused. + * + * Return: Length of buffer written + */ +static ssize_t getenforce(struct file *f, char __user *data, + size_t len, loff_t *offset) +{ + const char *result; + + result = ((READ_ONCE(enforce)) ? "1" : "0"); + + return simple_read_from_buffer(data, len, offset, result, 1); +} + +/** + * new_policy() - Write handler for the securityfs node, "ipe/new_policy". + * @f: Supplies a file structure representing the securityfs node. + * @data: Supplies a buffer passed to the write syscall. + * @len: Supplies the length of @data. + * @offset: unused. + * + * Return: + * * Length of buffer written - Success + * * %-EPERM - Insufficient permission + * * %-ENOMEM - Out of memory (OOM) + * * %-EBADMSG - Policy is invalid + * * %-ERANGE - Policy version number overflow + * * %-EINVAL - Policy version parsing error + * * %-EEXIST - Same name policy already deployed + * * %-ENOKEY - Policy signing key not found + * * %-EKEYREJECTED - Policy signature verification failed + */ +static ssize_t new_policy(struct file *f, const char __user *data, + size_t len, loff_t *offset) +{ + struct ipe_policy *p = NULL; + char *copy = NULL; + int rc = 0; + + if (!file_ns_capable(f, &init_user_ns, CAP_MAC_ADMIN)) { + rc = -EPERM; + goto out; + } + + copy = memdup_user_nul(data, len); + if (IS_ERR(copy)) { + rc = PTR_ERR(copy); + copy = NULL; + goto out; + } + + p = ipe_new_policy(NULL, 0, copy, len); + if (IS_ERR(p)) { + rc = PTR_ERR(p); + goto out; + } + + rc = ipe_new_policyfs_node(p); + if (rc) + goto out; + +out: + kfree(copy); + if (rc < 0) { + ipe_free_policy(p); + ipe_audit_policy_load(ERR_PTR(rc)); + } else { + ipe_audit_policy_load(p); + } + return (rc < 0) ? rc : len; +} + +static const struct file_operations np_fops = { + .write = new_policy, +}; + +static const struct file_operations audit_fops = { + .write = setaudit, + .read = getaudit, +}; + +static const struct file_operations enforce_fops = { + .write = setenforce, + .read = getenforce, +}; + +/** + * ipe_init_securityfs() - Initialize IPE's securityfs tree at fsinit. + * + * Return: %0 on success. If an error occurs, the function will return + * the -errno. + */ +int __init ipe_init_securityfs(void) +{ + int rc = 0; + struct ipe_policy *ap; + struct dentry *dentry; + + if (!ipe_enabled) + return -EOPNOTSUPP; + + root = securityfs_create_dir("ipe", NULL); + if (IS_ERR(root)) + return PTR_ERR(root); + + dentry = securityfs_create_file("success_audit", 0600, root, + NULL, &audit_fops); + if (IS_ERR(dentry)) { + rc = PTR_ERR(dentry); + goto err; + } + + dentry = securityfs_create_file("enforce", 0600, root, NULL, + &enforce_fops); + if (IS_ERR(dentry)) { + rc = PTR_ERR(dentry); + goto err; + } + + policy_root = securityfs_create_dir("policies", root); + if (IS_ERR(policy_root)) { + rc = PTR_ERR(policy_root); + goto err; + } + + ap = rcu_access_pointer(ipe_active_policy); + if (ap) { + rc = ipe_new_policyfs_node(ap); + if (rc) + goto err; + } + + dentry = securityfs_create_file("new_policy", 0200, root, NULL, &np_fops); + if (IS_ERR(dentry)) { + rc = PTR_ERR(dentry); + goto err; + } + + return 0; +err: + securityfs_remove(root); + return rc; +} -- cgit v1.3.1